Fossil hunters removed a hundred tons of rock by hand last summer to extract the skeleton of a huge pliosaur in Norway's Svalbard archipelago.

Revealed to the public on February 27, 2008, the "sea monster" is one of the biggest marine reptiles ever found. It was discovered at the site of 40 other large Jurassic-era sea creatures some 800 miles (1,300 kilometers) from the North Pole.

The reptiles swam in temperate seas and sank to the ocean floor after they died, where their bodies were preserved in soft mud, according to expedition leader Hurum.

The pliosaur's fossil bones have been softened by freezing Arctic conditions, Hurum noted.

"They are almost like gravelthey have been frozen and thawed many, many times."

So far, 6.5 gallons (25 liters) of glue have been used to stabilize the skeleton, he added.